Just finished a episode of the planet money podcast about international shipping ^^ if you got 22 min to burn i recommand a listen !
https://www.npr.org/sections/money/2018/08/01/634737852/episode-857-the-postal-illuminati
And it was a poorly planned, messily implemented, hamfisted attempt to combat this that lead to the utter disaster that was US international flats shipping this past year. Wheeeeee.